Metro 2 Account Type Code 0F: Construction Loan

Specification

Code	0F
Meaning	Construction Loan
Field	Account Type (Field 15)
Record	Base Segment
Length / position	2 chars · 84–85
Category	Secured and Collateralized Installment
CRRG reference	CRRG Exhibits 1 & 2 (Account Type Codes)

Funds work in progress. The balance grows through the construction period as draws are advanced, which is the opposite of a normal installment loan's amortization.
Reported as Portfolio Type I in the source table, even though the draw behaviour looks line-like. The account type does not become a line-of-credit code.
Does NOT cover the permanent mortgage that replaces it. When a construction-to-permanent loan converts, the permanent phase is a mortgage code such as 26.
Does NOT cover a home-improvement loan on an existing structure. That is 04, or 05 when FHA insured.
During the construction phase many programmes require interest-only payments, so the Scheduled Monthly Payment moves as the drawn balance moves.

1A community bank reports a 12-month construction loan on a new single-family home, disbursed in five draws against inspections.
2A credit union reports an owner-builder construction loan with interest-only payments during the build.
3A lender reports a construction-to-permanent loan under 0F during the build phase and converts the tradeline classification when the permanent phase begins.
4A regional lender reports a teardown-and-rebuild construction loan on a lot the borrower already owned.

Report Current Balance as the amount actually drawn, not the full construction commitment.
Report the total commitment in Highest Credit / Original Loan Amount so the tradeline shows the size of the obligation.
Update the Scheduled Monthly Payment when the payment changes as draws are advanced. A stale interest-only payment misstates the obligation.
When a construction-to-permanent loan converts, follow your programme's convention consistently. Do not switch classification for some loans and not others.
Do not report a construction loan under a mortgage code while it is still in the construction phase if you are following the Appendix A Portfolio Type I classification.

A file can be structurally valid and still be wrong. These are the cross-field conditions Account Type Code 0F has to satisfy.

Portfolio Type must be I (Installment), so Scheduled Monthly Payment Amount and a numeric Terms Duration in months are both required even though the loan behaves like a draw facility.
Credit Limit must be zero-filled despite the draw behaviour. The commitment amount belongs in Highest Credit, not Credit Limit.
Current Balance rising month over month is expected here and is not a data error, which is unusual for Portfolio Type I and worth documenting in your own validation rules.
The K3 segment is not reported during the construction phase, since the account is Portfolio Type I rather than M.
Terms Duration should reflect the construction term (often 12 or 18 months), not the eventual permanent term.
When the loan converts to permanent financing, the mortgage code and Portfolio Type M bring the K3 segment into play at that point.